This invention relates to the art of lithium batteries, and more particularly to a new and improved insulating arrangement and method for preventing internal loading and short circuiting in such batteries.
One area of use of the present invention is a multi plate lithium battery for delivering high current pulses, although the principles of the present invention can be variously applied. In lithium batteries wherein the lithium anode and the outer conductive case are at the same electrical potential, it has been determined according to the present invention that internal loading and short circuiting can result from formation of lithium clusters between cathode and anode surfaces. In particular, in prior lithium battery designs a cell stack assembly comprising a plurality of cathode plates with anode sections interposed therebetween was placed into a bag of insulating material. Cathode bridge components associated with the arrangement for electrical connection to the cathode plates and separator components were isolated from contact with other electrically conductive materials through the use of insulating straps strategically placed over the components.
Although the foregoing design functions well, skill is required to assemble such components. In addition, parts may shift in later handling and assembly operations, thus requiring an inordinate amount of care in further assembly. Such shifting of parts can expose the cathode bridge thereby providing a direct path between anode and cathode surfaces along which the above-mentioned lithium clusters can form.
It would, therefore, be highly desirable to provide a barrier which blocks such direct path between anode and cathode surfaces and which effectively isolates components of different electrical potential thereby preventing internal loading and short circuiting caused by lithium cluster formation.